Phonogram-blank



UNITED STATES PATENT OFFICE.

THOMAS A. EDISON, oF LLEWEL YN PARK, NEW JERSEY.

PHONOGRAM-BLANK'.

SPECIFICATION forming part Of Letters Patent N0. 430,274, dated J' 11116 17, 1890.

Application filed July 30, 1888. Serial No. 281,454. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS A. EDISON, of Llewellyn Park, in the county of Essex and State of New Jersey, have invented a certain new and useful Improvement in Phonogram- Blanks, (Case No. 793,) of which the following is a specification.

My invention relates to phonogram-blanks for receiving a record of sound-vibrations and reproducing the same; and my object is to produce blanks having superior qualities for recording and reproducing such vibrations.

To this end my invention consists, mainly, in making such blanks, which are preferably of cylindrical form, of soap of the character hereinafter described. Said material may be employed alone or mixed with other materials, such as waxes, resins, or gums.

Insoluble soap may be formed of any metal or sometimes of an earthy oxide, like lime, in combination with any fatty acid. For my purpose, however, it is best to use lead, magnesium, or aluminium, combined with oleic or stearic acid, forming an oleate or stearate of the metal used. These compounds are preferred because of their superior amorphous quality. Of the metals named I especially prefer to employ lead, and especially to use a mixture of equal quantities of oleate and stearate of lead, the same being melted and poured into molds to form the cylindrical blanks.

The soap may be made according to the usual well-known methods.

What I claim is 1. Phonogram -blanks made of metallic soap, substantially as set forth.

2. Phonogram-blanks made of lead soap, substantially as set forth.

3. Phonogram-blanks made of a mixture of oleate and steal-ate of lead, substantially as set forth.

This specification signed and witnessed this 14th day of July, 1888.

THOS. A. EDISON.

Witnesses:

WILLIAM PELZER, A. W. RIDDLE. 

